They have left their rural homes for the towns and cities. Many of them have moved from one city to another. There are an estimated 100 million migrant workers in China. One fifth of Beijing's population of 15 million are migrant workers.
They are mainly employed in construction, housekeeping or garbage collecting. In a word, they have taken over the hardest and dirtiest jobs that many locals will not do.
Producer:Duan
Lei & Allen Chai 
Lin is a tricycle rider in Beijing. He came to the city with his wife from a small village in Anhui Province three years ago. His main work is driving the "tricycle taxi". Sometimes he collects garbage. His wife is also doing the same work.
41-year-old Lei is a repairman in a real estate company. He came to Beijing from central China¡¯s Henan Province and has been here for nine years. Now the middle-aged man is facing a dilemma. He has to make a decision about whether to go home or not.
Beijing's Number One Blue Sky Middle School is a school for children of migrant workers in the city. There are 15 classes, each with about 30 students.
Dou Jinkai was born in the countryside near the provincial capital of Changchun. Now the young man owns a beauty salon in a four-star hotel in one of the busiest commercial areas in downtown Beijing.
